What are the solutions to the system

Suppose you are an avid reader and are looking to save money on the cost of books instead of paying about $20 for each book, you decide to look into purchasing a kindle for $120 you can purchase e-books for about $5 each 1. find the slope-intercept equation for the cost of the hard copy of books using x to represent the number of books 2. find the slope-intercept equation for the cost of the kindle with cost of e-books using x to represent the number of books

The functions f(x) and g(x) are shown in the graph f(x)=x^2 what is g(x) ?

For the right triangle shown, the lengths of two sides are given. find the third side. leave your answer in simplified, radical form.